Multiband gridded focal plane array antenna

Abstract

A multiband gridded focal plane array antenna 10 is disclosed which provides simultaneous beams of multiple frequencies. The antenna 10 includes a metallization pattern 11 providing a first set of conductive edges 18 having a first length L 1 and a second set of conductive edges 20 having a second length L 2 . The first and second sets of conductive edges are separately fed to provide the first and second simultaneous output beams at first and second operating frequencies.

What is claimed is: 
     
       1. A multiband antenna, comprising: a metallization pattern disposed on a first surface of a dielectric substrate, said metallization pattern including a first set of conductive edges having a first length, a second set of conductive edges having a second length, and a third set of conductive edges having a third length;   first means for coupling electromagnetic energy of a first operating frequency to said first set of conductive edges;   second means for coupling electromagnetic energy of a second operating frequency to said second set of conductive edges;   third means for coupling electromagnetic energy of a third operating frequency to said third set of conductive edges; and,   wherein said first set of conductive edges, said second set of conductive edges, and said third set of conductive edges collectively define a grid, said first set of conductive edges providing outer edges of said grid, said second set of conductive edges providing inner edges of said grid, with said inner edges being interconnected to provide a set of inner apertures, and said third set of conductive edges being disposed within said inner apertures.   
     
     
       2. The antenna as set forth in claim 1, wherein said third set of conductive edges are provided by patches of conductive material. 
     
     
       3. The antenna as set forth in claim 2, further comprising a fourth set of conductive edges having a fourth length. 
     
     
       4. The antenna as set forth in claim 3, wherein said fourth set of conductive edges are disposed within said inner apertures of said grid. 
     
     
       5. The antenna as set forth in claim 4, wherein said fourth set of conductive edges are provided by patches of conductive material. 
     
     
       6. The antenna as set forth in claim 5, further comprising a fifth set of conductive edges having a fifth length. 
     
     
       7. The antenna as set forth in claim 6, wherein said fifth set of conductive edges are disposed within said inner apertures of said grid. 
     
     
       8. The antenna as set forth in claim 1, wherein said second means for coupling electromagnetic energy to said second set of conductive edges comprise resonators mounted to a second surface of said dielectric substrate. 
     
     
       9. The antenna as set forth in claim 8, further comprising transmission line means mounted to said dielectric substrate for directly feeding said electromagnetic energy to said resonators, said electromagnetic energy then being coupled to said second set of conductive edges.